Answer:
- -28y^4 - 7y^3 + 62y^2 + 5y - 30
Step-by-step explanation:
<u>Opening the parenthesis and simplifying by combining like terms:</u>
- (6 - y - 4y^2)(-5 + 7y^2) =
- 6(-5) +6(7y^2) - y(-5) -y(7y^2) -4y^2(-5) -4y^2(7y^2) =
- -30 + 42y^2 + 5y - 7y^3 +20y^2 -28y^4 =
- -28y^4 - 7y^3 + 62y^2 + 5y - 30
Answer:
Mean = 1.42
Variance = 0.58
Step-by-step explanation:
Given: X denote the number of luxury cars sold in a given day, and Y denote the number of extended warranties sold.
Also, joint probability function of X and Y are given.
To find:
mean and variance of X
Solution:
From the given joint probability function of X and Y,

Mean of X:

Variance of X:

![var(X)=E\left [ X^2 \right ]-\left ( E\left [ X \right ] \right )^2\\=\frac{31}{12}-\left ( \frac{17}{12} \right )^2\\=\frac{31}{12}-\frac{289}{144}\\=\frac{372-289}{144}\\=\frac{83}{144}\\=0.58](https://tex.z-dn.net/?f=var%28X%29%3DE%5Cleft%20%5B%20X%5E2%20%5Cright%20%5D-%5Cleft%20%28%20E%5Cleft%20%5B%20X%20%5Cright%20%5D%20%5Cright%20%29%5E2%5C%5C%3D%5Cfrac%7B31%7D%7B12%7D-%5Cleft%20%28%20%5Cfrac%7B17%7D%7B12%7D%20%5Cright%20%29%5E2%5C%5C%3D%5Cfrac%7B31%7D%7B12%7D-%5Cfrac%7B289%7D%7B144%7D%5C%5C%3D%5Cfrac%7B372-289%7D%7B144%7D%5C%5C%3D%5Cfrac%7B83%7D%7B144%7D%5C%5C%3D0.58)
The route to an ancient pyramid is 79 miles long; if 20 miles is travelled each day for 3 days, the distance travelled in the fourth day would be 19 miles.
<h3>What is an equation?</h3>
An equation is an expression that shows the relationship between two or more numbers and variables.
Let the distance travelled in the first day be 20 miles. If the same time was travelled for 3 days, hence:
3(20) + x = 79
x = 19 miles
The route to an ancient pyramid is 79 miles long; if 20 miles is travelled each day for 3 days, the distance travelled in the fourth day would be 19 miles.
Find out more on equation at: brainly.com/question/2972832
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The square of a whole number n lies between 80 and 150, so n lies between √80 and √150.

n is a whole number and lies between 8.9 and 12.2, so n can be 9, 10, 11, or 12.
The possible values for n are 9, 10, 11, and 12.